1. Field of the Invention
The invention relates to a method for compensating for thermally induced deformation of a press cylinder. The invention also relates to a press cylinder having a base body with a radially outer surface and a temperature control means for compensating thermally induced deformation of the press cylinder.
2. Description of the Related Art
During a printing operation, thermally induced deformation can develop in the press cylinders of a printing press, especially on the outer surfaces of the cylinders, and this can have an adverse effect on the attainable printing result. This phenomenon can be observed especially in relatively long blanket cylinders of small diameter on which blankets or blanket plates are clamped in a lockup slot. In blanket cylinders of this type, thermally induced deformation of the press cylinder occurs in a circumferential area that is closer to the trailing edge than to the leading edge of the blanket. In the case of blanket cylinders, the maximum thermally induced deformation of the cylinder typically occurs in a circumferential area about 270° from the leading edge and thus about 90° from the trailing edge of the blanket. During the printing operation, the blanket cylinder heats up most strongly in this circumferential area, and this leads to deformation of the press cylinder.
Practical examples of press cylinders are already known in which the temperature can be controlled uniformly around the entire circumference in an area that lies radially inward from the outer surface of the cylinder. In press cylinders of this type, however, it is impossible to compensate effectively for thermally induced deformations of the cylinder.